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"We do not determine the guilty; we do not decide the punishment; we are merely the cold instruments of the Emperor's vengeance. There is no form of death unknown to us; there is no form of terror beyond our means; there is no enemy outside our reach. We are the blade that hovers over the throat of the traitor; we are the bullet that awaits the heretic's skull; we are the poison in the throat of the alien."

— Decree Assassinorum

The Officio Assassinorum is a highly secretive agency within the Imperium of Man's Adeptus Administratum that employs different "temples" that train Human Assassins to further the goals and protect the security of the Imperium. Although the Inquisition strikes fear in the hearts of all Imperial citizens, loyal and corrupt alike, the deadly disciples of the Officio Assassinorum strike fear in the hearts of even the most savvy, battle-hardened of Imperial warriors.

Assassins are typically deployed alone wherever feasible, having been trained to operate extensively behind enemy lines with no support. Given the sheer potential political power of this adepta and the fact that its operatives are known to have been used against rival High Lords of Terra in the past, the authorisation to assassinate a target must come from the very highest echelons of Imperial command. For this reason, Assassins are watched very closely to make sure that they are always under the control of the Imperium and serving the will of the Emperor.

Almost nothing is known in Imperial databases about the locations of the Officio Assassinorum's six different headquarters or "temples" except that they are still located somewhere on Terra, save for the Eversor Temple. The Eversor Temple does not maintain a single headquarters and instead keeps its operatives in cryo-stasis on a variety of secret starships and space stations that are scattered across Imperial space and maintained on high-alert for the assignment of a mission at any time.


Assassinorum Icon 2

Icon of the Officio Assassinorum

The Imperial Assassins are the hidden blades wielded by the High Lords of Terra. They are the slayers of kings and false messiahs, the bane of Traitors and rebels across the stars. Once an agent has been despatched, they are as relentless and inescapable as the march of time itself. Every facet of their impeccable training is turned to the business of a single kill. Though the temples of the Officio Assassinorum are shrouded in the utmost secrecy, all men and women of influence fear the shadows they cast, for their operatives are the Emperor's justice made real. In a realm the size and scope of the Imperium, it is all too common for planets to escape the vigil of the High Lords.

With communication and travel at the mercy of the Warp's shifting tides, a populace can go for ten, twenty, even a hundred standard years without being contacted by the wider Imperium. It is a fragile system indeed, and given the crushing grind of much of Imperial life, one that has seen many worlds fall into the thrall of heresy. Left to fend for themselves against a hostile galaxy, it is easy for a planet's citizenry to harbour the seeds of corruption. A world may fail to pay its Imperial tithes, allow its psyker containment routines to slip, or come under the rule of an unsanctioned or secessionist planetary government. Some simply crave independence away from the dictates of the Administratum, the Ecclesiarchy, and a galaxy ruled by twelve faceless figures in the name of a distant God-Emperor.

Regardless of whether the new order is benevolent or tyrannical, its orchestrators make themselves targets for the most violent of retributions. Though their government may thrive in the short term, word will eventually reach the adepts of the Imperium of their disobedience. Sometimes the resultant confrontation leads to open war, but it is just as often resolved by covert means. Coercion, bribery, threats, blackmail and murder are all weapons in the armoury of those whose iron grip defines the realms of Mankind. To this end, the Imperium has developed several institutions to exploit these weapons to their fullest; ancient organisations that trace their history back to the Great Crusade and the very birth of the Imperium. One such organisation is the Officio Assassinorum.


An organisation chart showing how the Officio Assassinorum is organised beneath the Administratum. Note that the Venenum Temple and the Vanus Temple are classified on this chart. The Renegade Maerorus Temple is not shown as it is no longer in existence.

The Assassins of the Imperium are able to change the fate of worlds with the pull of a single trigger. Where the length of the Emperor's reach needs to be made abundantly clear, a Vindicare Temple sniper will put a bullet in the target's head whilst the errant individual is surrounded by his followers.

If the traitorous creed has spread to an entire organisation or military force, an Eversor Assassin will instead be set loose; a bio-enhanced berserker that will slaughter dozens if not hundreds of rebels alongside the key individual they have been sent to slay. Should the deed require more subtlety, an operative from the Callidus Temple will instead be despatched; in such cases it is all but impossible to detect the presence of these shape-shifting Assassins until the deed is done. If the target is a psyker, one of the rare and fearsome Culexus Assassins will be sent to hunt them down -- beings with a strange void in place of a soul that makes them the bane of all who treat with the Warp.

The weapons of the Assassins range from simple knives and garrotes, to exotic neural shredders and phase swords that can cut through armour and force field alike. Even barehanded, these operatives are lethal foes; each is trained extensively in unarmed combat and is more than capable of fighting their way free from the mayhem that ensues from their kill.

Returning to their masters, they are extensively debriefed and examined before being given a new mark and mission to accomplish. In this way, each Assassin is locked into a constant cycle of headhunting that spans the breadth of the Imperium, reforging the fragile chains of Imperial rule even as the Era Indomitus in the 41st Millennium breaks them apart.

Founding of the Officio Assassinorum

"No world shall be beyond my rule; no enemy shall be beyond my wrath."

— The Emperor of Mankind upon the summit of Mount Vengeance on the world of Thor, circa M30, from the first page of the Grimoire Assassinorum
Officio Assassinorum symbol 2

Alternative icon of the Officio Assassinorum

When the Emperor spoke this famous declaration during the early years of the Great Crusade, a number of his most loyal servants met, eager to help enact his dreams of uniting Mankind across all the settled worlds of the galaxy. These men and women were highly skilled in the craft of stealth and subterfuge and highly accomplished in the arts of death.

They hunted down those who would bring ruination to the Emperor's plan for Human betterment. In secrecy they acted, preferring not to receive praise from the Emperor for their actions, for they felt themselves unworthy of such attentions amidst the great sacrifices and destruction caused by the ongoing operations of the Great Crusade. They carried out their executions silently, moving unseen from world to world in the wake of the Emperor's conquest, ensuring that promises made to the Imperium by rulers newly brought into Imperial Compliance were not reneged upon, that newly installed planetary governors remained loyal, and that treaties and pacts were enforced.

In time, these servants realised that they could not hide from even their own deaths forever, and that their skills must be passed on to a new generation if their great work was to continue. Thus, they finally revealed their existence to the Emperor. He saw, sorrowfully, the necessity for their existence and the terrible duty that they had taken upon themselves and he was most pleased. Great temples were constructed and the most skillful and deadly youths were sought out to train at them.

Thus was the Officio Assassinorum created in secret, and the names of Callidus, Venenum, Culexus, Vindicare, Eversor and Vanus were forever immortalised. The strongest survived their rigorous training, and in turn passed on their skills to others. New skills were learnt and new temples of death were later founded; the art of blade and pistol, poison and garrote were honed in every aspect conceivable. So it is that there is no world in the galaxy beyond the Emperor's rule; no enemy beyond the Emperor's wrath.

During its early history all six Assassinorum Temples, then known as "clades", were located on Terra. Each clade was led by an official known as its "director primus." The Officio Assassinorum was created during the Great Crusade in the 30th Millennium by Malcador the Sigillite, the Regent of Terra, who served as its first overall leader or "Grand Master of Assassins" on the order of the Emperor. The Assassins of all 6 existing clades were tasked by the grand master and their founding directors primus with carrying out the Imperium's goals in those circumstances where unleashing the full military forces of the Imperium would prove unwise or too costly.

The Assassinorum clades came into their own during the Horus Heresy of the early 31st Millennium, when they were tasked with eliminating the rebel Warmaster Horus and other leaders of the forces of Chaos; these missions met with only mixed success as the brutal history of that period all too amply demonstrates.

However, after the Wars of Vindication which took place shortly after the death of High Lord Goge Vandire during the Age of Apostasy in the 36th Millennium, a renegade Callidus Assassin by the name of Tziz Jarek attempted to assassinate the Grand Master of Assassins of that era. After a series of terrible atrocities that were precipitated within the Imperial Palace itself, the Assassin temples were split up and distributed across the width and breadth of the galaxy.

This was to ensure that should one fall to alien influence, Daemonic influence, or other heresy, the others would remain untainted. Similarly, a hidden ordo of the Inquisition was implemented, known as the Ordo Sicarius, to monitor the Officio Assassinorum, and its power was drastically limited -- assassinations could only be performed after receiving a 2/3 vote from the Senatorum Imperialis of the High Lords of Terra. All Assassins were to give detailed accounts of their mission activity, subject to Inquisitorial inspection at any time. Lastly, all Assassins (with the exception of those of the Eversor Temple) were to undergo regular psycho-indoctrination, again under the scrupulous eyes of the Inquisition if deemed necessary.

Notable Assassinorum Actions

Officio Assassinorum Seal

Another variant Officio Assassinorum seal

Over the course of the Imperium's history, the agents of the Officio Assassinorum have claimed millions of lives for their masters. But their tactics differ greatly from the worldwide slaughter brought to bear by the Astra Militarum or the unremitting force of an Adeptus Astartes strike. Each death they bestow upon the enemies of the Imperium is a carefully crafted link in the chain that binds the realm of Humanity to the Emperor's immortal will.

Though every one of these kills is extensively documented in the appropriate temple's datacrypts, only a very small fraction have entered the legends of the Imperium, known by few outside the vaulted halls of the High Lords themselves.

  • The Horus Heresy (ca. 005-014.M31) - After the Warmaster Horus' treachery is revealed, an early incarnation of the Officio Assassinorum sends four operatives, one from each of the major temples, to form an Execution Force and hunt down and destroy the Traitor Primarch. All four are found wanting, for Horus is powerful beyond the reach of mortal men, and his destiny lies elsewhere.
  • Death of a Primarch (ca. M31) - The Primarch of the Night Lords, Konrad Curze, is plagued by visions of his own future demise -- a kill-strike that will be ordered by the Emperor Himself. The knowledge of his genetic father's future betrayal festers within him, and he eventually becomes the fiendish Traitor Primarch known as Night Haunter. As the Heresy unfolds, the Callidus Temple is charged with the Primarch's death. Though his Legionaries fight to catch the killer in their midst, the Assassin M'Shen enters Night Haunter's throne room to find him unresisting. By allowing the Emperor to kill His own son, the creature that was once Konrad Curze believes his rebellion vindicated forever -- for in death, he has proved the Emperor is as callous as he has always maintained.
  • The Beheading (546-646.M32) - The High Lords of Terra are slain to a man when the Grand Master of the Officio Assassinorum, Drakan Vangorich, mounts a bloody coup solar decades in the making. Thus begins a hundred-year period of anarchy in which the Imperium is all but torn apart. It is only at great loss that a Space Marine retribution force delivers the Emperor's justice to Vangorich and his Acolytes. In the aftermath, over fifty Space Marine leaders arrive upon Terra, accompanied by a Crusade-strength "honour guard." After a long council with the great and the good behind closed doors, twelve new High Lords are placed in office, and stability thus returns to the Imperium.
  • A Ghost Amongst Devils (990.M32) - The Culexus Assassin Dranos is sent to destroy the Chaos Sorcerer Xantaka before he can conjure any more daemonic legions from the Warp. Being all but invisible to not only the aether-sight of Xantaka's Daemon armies but also his Rubricae bodyguard, Dranos simply walks up to the Sorcerer Xantaka and burns his brains to ash with a blast of negative energy.
  • Mother Gullet (340.M33) - A Callidus Assassin, sent to steal away the firstborn child of the dangerously self-centred planetary Ggovernor Thygmus van Spracht, disguises herself as the infant's matron-vigilus. By widening her craw with Polymorphine and swallowing the princeling whole, she walks past the elite Palace Guards without so much as a whisper of resistance. She carries the prize in her belly to her masters before regurgitating it whole, mewling but safe. Pict-skull footage is sent to the governor, and he falls back into the Imperial fold within the week.
  • The Blinded Seer (452.M34) - A Culexus Assassin is sent to claim the head of the manipulative Farseer Lithandros-Esmanthil. The Eldar senses the threat and scries the skeins of fate accordingly, but is increasingly alarmed to find he is unable to locate the thread corresponding to his pursuer. After a long and terrifying hunt, the Assassin ambushes his prey in the lonely halls of Saim-Hann's Dome of Reflection. Rendered psychically inert and driven to exhaustion by the chase, Lithandros-Esmanthil gives himself up to the sinister violence that follows.
  • Cull of the Goliaths (372.M35) - The Abhuman Goliaths of Thugrock Secundus, a recruitment moon for the Astra Militarum, develop a blood cult that consumes the planet's ruling caste. In an unprecedented display of miscommunication, no fewer than six Eversor Assassins are dispatched to slay the leaders of the indigenous population. By the time the single surviving Eversor is recovered, not one Thugrock Goliath is left alive, and when the news reaches the Astra Militarum, they are most displeased that such a rich resource has been wasted. To this day, the event is used as a cautionary fable to illustrate the dangers of despatching several Assassins at once.
  • The Reign of Blood (ca. 200.M36) - Goge Vandire, Ecclesiarch and High Lord of the Adeptus Administratum, falls from the Emperor's light. His tremendous influence, charisma and determination to overhaul the Imperium sparks a civil war that lasts for seven decades. His insurrection only ends when a counter-crusade mounted by Sebastian Thor tears power from the Traitor's cold and clutching claws.
  • Death of a Recidivist (501.M37) - The influential Cardinal Jerome the Unsaintly of Oristia IV secedes from the Imperial Creed. He amasses an insane amount of wealth through illegal levies, hoping to gather an army of Frateris Militia to rival that of Goge Vandire. He is shot in the roof of the mouth by a Vindicare Assassin whilst singing subversive hymns.
  • The Morisha Incident (563.M37) - Urhua Thereaux, Assassin of the Venenum Temple, is dispatched to assassinate the Renegade Governor Yawell of Morisha. During transit, the starship is caught in a Warp rift, holding the vessel in temporal stasis for some six hundred and ninety-eight standard years. Not knowing that this has occurred, Thereaux proceeds to her target, only to find Yawell long since dead and replaced by an anti-Imperial democratic committee consisting of over a thousand members. Faced with such an extreme task, Thereaux only succeeds in killing the committee members after spending three solar days poisoning all the chairs in the council's auditorium prior to a meeting of the full committee.
  • The Stargazer's Demise (003.M38) - The progressive astrologer Lenas Scard is marked for death before his heretical discoveries shake the Imperial Creed any further. The Vindicare Assassin Erasmus Menst hangs upside down from a Promethium relay pipe for six solar days, awaiting his prey, only to realise that Scard is aware of his pursuit and has holed up inside his observatory. Menst abandons his plan and instead climbs to the highest spire of Hive Mendicantus, knowing that it is only a matter of time before the glint of Scard's scrying scope appears. Sure enough, as the planet's moon is bisected by the spire, a telltale flash from Scard’s observatory appears. Menst is able to put a shot through the telescope's lens and into the eye socket of the stargazer behind it.
  • Fall of Orlenza Triartes (386.143.M38) - The planet of Orlenza Triartes severs its ties from the Imperium, hoping for better trade terms. The Planetary Governor tricks his Adeptus Arbites into quelling a prison break that turns out to be a carefully crafted ambush, placing the Arbitrators under lock and key alongside those same criminals they had arrested. Word reaches the Imperium, and two regiments of Imperial Guard are sent to intervene. The preening aristocrats at the heart of the rebellion muster their forces and attack, only to find that their chief military advisor, a vulgar but effective mercenary known as Le Kard, was not who they thought he was. The Orlenza forces find their dispersal to be extremely ineffective, and they are surrounded and cut off within a solar week. When Le Kard's airtight cell is opened it is found to contain only a set of discarded clothes and a synskin-clad Callidus Assassin, crouching like a hyper-felid ready to pounce. The Assassin cuts a swathe through the planet's nobility before disappearing without a trace.
  • The Grot That Turned (209.M38) - The petite but fearsome Callidus Assassin Militzia Scarvelli infiltrates Big Mek Oilguzla's workshops in the guise of a Gretchin slave-creature. Just as Oilguzla launches his Deff Dread horde at the Space Marines protecting Hive Imperator, Scarvelli recovers her phase sword from its hiding place in a nearby stack of scrap metal and attacks. Though it takes her almost a full solar minute to do so, she hacks the Big Mek into fist-sized chunks before overloading his force-field generator and bringing the stomping advance of the Deff Dread mobs to a grinding halt.
  • Statuesque (243.M39) - The Vindicare Temple is given a kill order to take out the predatory Dark Eldar pilot known as the Skyknife. Knowing that to enter Commorragh would be to court almost certain failure, the Vindicare Assassin Dejedris Garamach determines the site of a previous sighting of the Skyknife's Razorwing jetfighter. He mounts his vigil in the eye socket of the Threndian Colossus, subsisting on moss and the raw flesh of the birds that use the statue as its nest whilst never taking his eyes from the sky. Six standard years later, his vigil is rewarded when the Skyknife appears from midair in a flash of azure light. Within a half-second of its appearance Garamach puts a turbo-penetrator round into the cockpit, killing the pilot instantly.
  • To Slay a WAAAGH! (718.924.M40) - The Ork Warlord Urgak the Unstoppable is on the verge of completing his Gargant and launching a WAAAGH! into the Vondiac Sector when a Vindicare Assassin sends a bullet into the reactor core of the giant effigy. The thing catches fire and then explodes spectacularly, killing not only Urgak himself but also the vast majority of the Meks in his employ. The WAAAGH! is halted before it even begins, putting the lie to Urgak's self-aggrandising title and plunging the surviving Orks into a bloody civil war.
  • The Tigers Caged (231.M41) - Hetman Grettch of the 593rd Kadaveran Tigers becomes so incensed at constantly being interrupted by the Tactical Auto-Reliquary of Tyberius that he "accidentally" deactivates it with a ceremonial mace. It is the first step in a rebellion that sees not only the 593rd, but the entirety of the Kadaveran Tigers, turn against the Imperium. A Callidus Assassin is sent to infiltrate Grettch's advisor corps, assuming the identity of his eyeless astropath before killing the traitorous commander and taking his place. When the Tigers open hostilities against the Cadian 342nd, their orders suddenly become contradictory and counter-intuitive, and when the command staff is obliterated by an artillery strike called down upon their own position, the entire rebellious war effort falls to pieces. The Kadaverans, their forces decimated within the hour, quickly see the error of their ways and submit themselves for a regiment-wide court martial. Though the Tactical Auto-Reliquary is recovered and later repaired, they are found guilty and executed to a man.
  • A Destiny Denied (290.M41) - The Officio Assassinorum, having failed to destroy the obscenely powerful Chaos Lord Malfecius with operatives from the Eversor and Vindicare Temples, sends the Culexus Assassin Vaedrex instead. The Culexus haunts the steps of Malfecius across the Eye of Terror. Only when Malfecius ascends to Daemon Princehood does Vaedrex finally strike. With Malfecius' latest incarnation rendering him vulnerable to Vaedrex' Psyk-Out Grenades, the Culexus finally manages to kill the reeling Daemon Prince with a punishing series of blasts from his Animus Speculum.
  • The Dread Gestalt (353.M41) - The Wyrdvane Psykers of the 122nd Vostroyan Firstborn come through a difficult Warp translation as a gestalt entity of terrifying psychic power. Revelling in their new abilities, they rise up amongst the ranks of their former comrades and enslave every one of them to their bloodthirsty desires. When the regiment arrives on Sylvanus II they set about the murder of the populace. The Hammers of Dorn are sent on a planetfall mission to destroy the Dread Gestalt, but the powers of the Wyrdvane Psykers are so swollen that the Space Marine attack is repelled with terrifying ease. Only when the Culexus Assassin known as the Revoker is unleashed into the Vostroyan ranks does the Dread Gestalt lose its power, flopping back to earth as weak as newborns. They are killed to a man by Vostroyan bayonets even before the Revoker can close with his target to finish the job.
  • Sons of the Interstice (886.M41) - The Lubricae Cult arises within the Adeptus Mechanicus, a body of Heretics that worship the interstitial substances that keep the universe running smoothly. All twelve of the senior Technomagi gather around a black and shimmering pool of arcanoil, anointing themselves with a mixture of war-virgin's blood and boiling grease as they declare open war on their former brethren. A slick black devil bursts from the pool's depths when the Eversor Assassin sent to slay them reveals himself. Within moments every one of the Lubricae Cult is slain. Their Skitarii legions attack nonetheless, but without leadership they are quickly defeated by their Loyalist counterparts.
  • The Foe Untouchable (ca. 999.M41) - Within the Eye of Terror, a Black Crusade of unprecedented size musters to break open the Cadian Gate. Rumours abound that its supreme warlord is empowered by the Gods of Chaos, and that whilst he enjoys their favour, he cannot be laid low by mortal weaponry. The agents of the Officio Assassinorum are dispatched en masse to slay the Warmaster of Chaos Abaddon and his most favoured lieutenants before they breach realspace. One by one they reach a succession of grisly ends, and still Abaddon remains at large as the 13th Black Crusade unfolds to devastating effect.


The Emperor's Knives

"An Assassin's body is his most powerful weapon. He can smash through steel with his hands and feet. He can climb sheer surfaces, leap gaping chasms, run as fast as the wind, and endure hardships that would kill a lesser man. None can withstand pain or hurt like an Assassin. He can place his hand in boiling lava without flinching, he can endure flame or cutting blade. Even mortal wounds will not blunt his purpose. He works silently and without thanks, for he is the bloody-handed and secret saviour of the Imperium."

The Nature of the Knife, Grand Master Relistocles

The training of an Imperial Assassin is a long and arduous business. Almost every recruit is an orphan, taken from the wreckage of his or her former life among the population of a Death World, Feral World or hive city, and transported to a local Schola Progenium for tutelage. There, they train alongside the youths who will become the foremost agents of the Imperium. Life in the scholas is extremely hard, a relentless grind of physical and mental challenge where only the strongest thrive. Taught to strive for excellence and obedience in all things, the minds and bodies of the recruits are sharpened to a killing edge whilst their spirit learns to embrace the Emperor as master and immortal father.

Most of these intense young men and women go on to train as Militarum Tempestus Tempestus Scions, commissars, Sisters of Battle or, in the most unusual cases, Inquisitors. Those of their number who are born killers, however, are instead appropriated by the shadowy figures that haunt each Selection Day. Those recruits are never seen again by their fellows. From that day onwards, their only true friend is death itself.

Training starts even as the Assassinorum ships return to Terra, with the Officio instructors testing their prospective pupils mercilessly. The recruits must survive on limited food or air for solar days at a time. They must constantly fight each other in armed and unarmed combat, in conditions of total darkness or blinding light, zero gravity or crushing weight, stifling heat or freezing cold. By the time of their arrival, there may be only a tenth of the prospective Assassins left, or sometimes -- if the instructors deem every recruit to be unworthy -- none at all.

Upon arrival at Terra, the surviving initiates begin the next stage of their training. Sailing past the space-borne basilicas, immense queues of pilgrim craft and military cordons that congest Terra's outer orbit, they are carried down into the Temples Assassinorum under the most advanced of shrouding protocols. In subterranean safehouses, these new recruits are divided amongst the hidden temples of the Officio Assassinorum.

Each temple has its own ancient ways and mysteries, and each specialises in a different aspect of the art of murder. There are many such temples, some of which are known to the others and some that remain completely secret. There, the initiates train for a full solar decade, labouring under the auspices of Lord Assassins so harsh they make the Drill Abbots of the Schola Progenium look like kindly uncles by comparison.

The training procedure becomes ever more rigorous over the years as the temples test each candidate to his or her utmost limits. Days are spent battling with bone-wrenching exercise engines, fighting in deadly bouts or mastering their tolerance for pain. Initiates must survive lengthy courses of psycho-indoctrination and aggressive hypnosis, undergo physical tests of ever-escalating severity, and digest vast quantities of information about the Imperium that will soon be their hunting ground.

They must train in the most esoteric of weaponry and steel their bodies against the ravages of endless steroids and stimms. Even then, they have only scratched the surface of their temple's potential arsenal. The hidden orders of the Assassinorum conceal masterpieces of destruction, some of which were devised by the primarchs, Malcador the Sigillite, and even the Emperor Himself. Truly, it is said that each temple houses a thousand deaths and more.

An Army of One

Execution Force

The Assassins of the four major temples of the Officio Assassinorum -- an Eversor Assassin, a Culexus Assassin, a Callidus Assassin and a Vindicare Assassin.

Unlike other warriors of the Imperium, who are able to focus on war and war alone, the Imperial Assassin must be truly autonomous. Once an operative is in the field, they must be able to cross the galaxy from one side to the other, by means fair or foul. They must not only master their own lethal calling, but also be proficient in a dozen others. They must know how to drive and sanctify everything from an armoured bike to a small spacecraft, must be able to convince truculent Machine Spirits to do their bidding, and clean, disassemble and reconsecrate their wargear whenever necessary.

They must have a professorial knowledge of the Imperium's history, organisation, and common languages. Their understanding of Human anatomy and physiology must be complete, and every fact the Imperium has uncovered about the physicality of the various xenos species is bequeathed to them under oaths of secrecy. Few Human minds can process such vast quantities of information, let alone master them. Not all survive the rigours of their training with their spirits intact, and many have fallen into madness at the sheer quantity of the trials they face. Yet an initiate that joins the ranks of their temple's full operatives will have all these skills at their command.

Key to the uncanny might of the Imperial Assassin is the surgery they must undergo during their ten standard years of tutelage. Augmentative nodes are stitched into their brain, and sub-muscular acoustic surgery prepares their body for the punishment that will be visited upon them in the line of duty. The level of arcane technology necessary is perhaps the most advanced the Imperium can provide -- for good reason, it is constrained to Holy Terra to minimise the chance of it being captured by the enemies of Humanity.

It is well that such ancient techno-magicks are revered so, and maintained with such painstaking care. Without them, the polymorphic drugs and reality-shifting devices used by the more esoteric temples would literally tear their operatives apart. Even if an Imperial Assassin survives their training, their leash is still held suffocatingly tight. Only by a successful petition to the High Lords of Terra themselves and a two-thirds majority in the subsequent vote can an Assassin be sanctioned and released into the galaxy to complete the task they were born to do.

The fact that the ultimate luminaries of the Imperium give their direct attention to the deployment of a single individual shows just how exceptional these killers are. The records of the Officio Assassinorum temples are as detailed as they are scrupulous, a source of great pride to the masters that watch over them. Across the millennia, occasions where the despatch of an operative has not resulted in the desired result are extraordinarily few and far between. Be the target man, witch, beast or Daemon, the result is the same, for an Imperial Assassin is death incarnate.


"For those that defy the Imperium, only the Emperor can judge your crimes. Only in death can your receive the Emperor's judgement."

— Motto of the Officio Assassinorum

There are four major Assassinorum "temples" in the 41st Millennium, originally known at the time of the Great Crusade and the Horus Heresy as "clades", each specialising in a different form or method of assassination.

Each temple is led by an official known as a "director primus" while the Officio Assassinorum as a whole is led by the Imperium's grand master of assassins.

Callidus Temple

Assassin Callidus

A Callidus Temple Assassin

The Callidus Temple is the subtlest of the ancient temples of the Officio Assassinorum, specialising in the artful deception of the enemies of the Imperium.

The methods of the Callidus Assassin are those of utmost cunning and duplicity. They are sometimes used on missions where overt interference by the Imperium would upset the intricate balance of power maintained by the High Lords of Terra.

It is quite possible for a Callidus operative to complete their task without the enemy force in question knowing they have been there at all. However, as the tumultuous times of the 41st Millennium consume the galaxy in the wake of the birth of the Great Rift, the Callidus Temple is making its presence felt upon the fields of battle more so than ever.

The techniques that the Callidus Temple uses to bring down its targets are many and diverse, and can go far beyond that of simply killing the perpetrator. The Callidus Temple undertakes many covert operations that may involve an Assassin infiltrating an enemy civilisation for solar weeks, months or even standard years.

Specialists in infiltration, deceit and impersonation, these Human chameleons will often take the place of a trusted aide or adjutant through their utmost mastery of disguise. To achieve the exacting tasks assigned to it, the Callidus Temple specialises in the use and development of the shape-altering drug polymorphine to enable its Assassins to undergo dramatic physical changes, altering their appearance to assume the features of any humanoid (of whatever gender).

Using this technique, the Callidus Assassin can get close to enemy commanders or powerful warlords, influencing their strategy and finally killing them when the opportunity arises. On the battlefield, they get as close to the chosen target as possible before making the kill at a critical time, often at the crux point of a conflict already in full flow.

With the commander of an enemy force suddenly slain, the balance of the battle can be skewed dramatically in favour of the Imperium.

Culexus Temple


A Culexus Temple Assassin.

The Culexus Temple is one of the most sinister and feared orders of the Officio Assassinorum and its Assassins have been described by the Aeldari as nothing short of pure evil. Its operatives are skull-helmed harbingers of death, nigh-invisible terrors whose merest touch can extinguish the victim's soul.

Even amongst the upper echelons of the Officio Assassinorum, this temple is always viewed with extreme caution. This is not because of the way that the Culexus operate, nor because of any particularly hideous methods they use to kill their targets. It is because of the Assassins themselves, for they are bearers of the Pariah Gene.

First and foremost, a potential Culexus Assassin is chosen because they possess a very rare genetic defect, something that is at once unique and yet utterly abhorrent to the Imperium. Every living being has some sort of presence in the Warp, where the soul is reflected through from the real universe.

For non-psykers this will usually be little more than a minute spark. For psykers, however, their soul blazes like a shining beacon that can be seen by other psykers and creatures that live within the Warp. The more powerful the psyker, the brighter their soul burns within the realm of the Empyrean.

Culexus Assassins are true terrors because they have, or appear to have, no presence in the Warp -– in its place, there is simply a void. They are, to all intents and purposes, soulless.

This extremely rare genetic defect occurs in less than one in a billion individuals. Those who suffer from this condition are known by the name of Pariah, Untouchable or psychic Blank, and meeting one is something that no normal Human being can ever forget.

Their cold calculating stare draws attention to their eyes; pools of blackness that seem to pull one into a pit of nothingness. The very presence of a Pariah makes those around them feel fearful and increasingly paranoid, as an all-pervading sense of wrongness causes skin to crawl and senses to rebel. Some may complain of excruciating head-pains, or steadily increasing levels of directionless panic, their hearts hammering and their breath coming in ragged gasps. For a psyker, this sensation is infinitely worse, manifesting as horrified panic attacks, seizures, and a monstrous sensation of being smothered or drowned.

Such horrible phenomena make Pariahs outcasts among Human society. And yet it is these very powers that the Culexus Temple refines and amplifies to create their terrifying Assassins. As a result, they can emit negative psychic energy that is deadly to psykers and Warp entities alike.

Culexus Assassins are usually deployed against psychic targets like Heretics, Asuryani Warlocks or even Daemons.

However, Culexus Assassins have been transformed by the Necrons into their foul Pariah servants by transferring their consciousnesses into necrodermis bodies.

Vindicare Temple


A Vindicare Temple assassin.

Vindicare Temple Assassins are cold, calculating killers that eliminate their targets with contemptuous ease. They aim to bring inglorious death to the enemies of the Emperor with a sniper's bullet, and have elevated the skills of the marksman to an art form.

It is said that a Vindicare can pick out a target's jugular vein or pupil from extreme range, even should the distance be traced through the ruins and smokestacks of an underhive sprawl. To complement their superhuman accuracy, the Vindicare Temple emphasises stealth and evasion techniques.

One of the temple's maxims is that a clean kill can only be made from an excellent firing position, and Vindicare Assassins have been known to occupy a given location for solar weeks, waiting for their quarry to reveal himself before finally taking the perfect shot. By meditating on the immortal glory of the Emperor, these superb marksmen can slow down their metabolism to an almost hibernatory state.

Though an operative's heart beats perhaps once per solar minute when in this state, subliminal triggers ensure he is roused into total focus the instant his target shows themselves.

In this way, the Vindicare can be likened to a spider or mantis, waiting motionless as stone before springing into action at the critical moment.

Eversor Temple


An Eversor Temple assassin.

The Eversor Temple is possibly the most gruesome weapon of the Officio Assassinorum. The temple specialises in shock and terror tactics, instilling fear of Imperial retribution in the hearts and minds of all who hold positions of power.

Eversor Assassins are primarily used against rebels who have plans to move against the Imperium with a large armed force. When the long, grinding war of attrition that is the Astra Militarum's forte is ruled out -- perhaps because it is likely to leave a valuable planet ravaged -- the High Lords will sometimes sanction the use of an Eversor Assassin.

An Eversor distills the brute force of an entire strike team into a single Human body, and hence rarely has just a single target. Their mission will be to rip the heart out of the rebel operation, wreaking havoc and destruction. Such brutality ensures that the Renegade leaders are destroyed in one fell swoop, and that no would-be successors may take over.

In order to better enact these one-man killing sprees, the Eversor Temple trains its operatives to be utterly ruthless and completely dedicated to the Imperium. The temple engineers its inductees to be superhuman killing machines, their bodies driven far beyond normal Human capabilities.

Once this process is complete, the temple introduces a range of stimms and cybernetic neural implants to alter the Assassin's state of mind into a boiling cauldron of murderous intent.

Other Temples

There exist two major temples of the Officio Assassinorum that specialise in untraceable kills, although not much information about them is available in Imperial records.

The Officio Assassinorum is also known to maintain patronage over numerous minor Assassin temples and death cults scattered across the galaxy. Though they do not have the pedigree of the Vindicare, Callidus, Eversor or Culexus, these temples are just as ferocious in their pursuance of the Imperial cause.

  • Adamus Temple - The Adamus Temple, originally known as the Clade Adamus, was the oldest of the clades of the Officio Assassinorum during the Great Crusade and Horus Heresy. It is unclear whether it has survived into the 41st Millennium as one of the Officio Assassinorum's present temples. Clade Adamus Assassins are master swordsmen and melee specialists, drawing on some of the most ancient blade-master traditions of Old Earth. Adamus Assassins were dedicated to decapitation strikes intended to eliminate an enemy military force's command and control.
  • Venenum Temple - The Venenum Temple trains exclusively in the use of exotic poisons and subtlety in carrying out their mission requirements. The Venenum Temple's stock-in-trade is employing operatives who are the galaxy's finest tox-artisans. Their mastery of poisons is unparalleled outside the Dark City of Commorragh, and the temple's operatives sow within their targets time-delayed toxins that afford them ample time to escape suspicion. Through their temple's apprenticeship they manufacture killing philtres from the most base of components, which allow them to terminate their targets and leave no metabolic trace of the toxin.
  • Vanus Temple - Almost nothing of the Vanus Temple is known beyond its name and the fact of its existence (though the High Gothic word "vanus" means "empty"). The Vanus Assassins are primarily used as intelligence-gatherers and in matters of grand strategy and intelligence tactics they are without peer, their political insight unparalleled by the scholars of the Imperium. The Vanus Temple works to engineer their mark's doom via their consummate command of information. The Vanus Temple wages a far more complex war, taking the art of the stealth kill to the next level. Their modus operandi is to learn everything possible about not only their target but also those closest to them, then to tacitly manipulate circumstances so that their mark's death is brought about by their own folly or -- preferably -- by the hand of a once-trusted friend or comrade. It is the Vanus Temple that the Imperium employs when the revelation of a prominent figure's heresy would cause more damage than the knowledge of the resultant retribution. Many a shining saint or vaunted figurehead has met with premature martyrdom after some secret heresy has reached the ears of the Vanus Temple. Perhaps the best summary of the Vanus Temple's philosophy was stated by Fon Tariel, an infocyte of Clade Vanus, the Vanus Temple's precursor, during the terrible civil war and intrigues of the Horus Heresy: "the cleanest kill is one that another performs in your stead with no knowledge of your incitement."
  • Maerorus Temple - The renegade and now-defunct Maerorus Temple was created in the early years of the 40th Millennium by the Officio Assassinorum to deal with multiple targets simultaneously, such as the command hierarchy of an enemy army, or the members of a particularly widespread Chaos Cult. In order to achieve this, the rogue temple turned to Hereteks to develop the use of illegal Human/mutant/xenos hybrids, including the possible use of Tyranid genetic material, in effect creating living weapons that were capable of absorbing the biomass of victims to rapidly evolve new bio-weapons through self-controlled mutation. This eliminated the need to maintain and utilise standard weaponry as such technology was always subject to failure. Ultimately, such techniques were considered gross, heretical violations of the Imperial Creed and the temple was eradicated when its first and only successful Maerorus Assassin, Legienstrasse, went rogue, believing that her power and near-immortality granted her the right to topple the Imperium itself. She was eventually slain at great cost on the remote world of Opis where she had taken refuge by an Imperial retribution force of Astra Militarum and Imperial Fists Space Marines commanded by Captain Darnath Lysander.
  • Temple Secretum - It is whispered that there exists a "Temple Secretum," an Assassinorum temple named for its dedication to keeping the Imperium's darkest secrets by any means necessary rather than for a preferred method of killing.


  • Assassinorum - Execution Force: Rulebook (7th Edition)
  • Codex: Assassins (2nd Edition)
  • Codex: Assassins (3rd Edition)
  • Codex: Daemonhunters
  • Codex: Grey Knights (5th Edition), pg.52
  • Codex: Necrons (3rd Edition), pg. 8
  • Dark Heresy: Ascension (RPG), pp. 139, 147-148
  • Dark Heresy: Daemon Hunter (RPG), pp. 54-55
  • Dataslate: Officio Assassinorum (Digital Edition)
  • Imperial Armour Volume Three - The Taros Campaign, pp. 142-143
  • Index Astartes II, "Bringers of Darkness - The Night Lords Space Marine Legion"
  • Inquisitor: The Thorians (Background Book) by Gav Thorpe
  • Warhammer 40,000: Rogue Trader (1st Edition)
  • Warhammer 40,000 Rulebook (5th Edition), pp. 121, 124
  • Warhammer 40,000 Rulebook (6th Edition), pp. 169, 180, 193, 403
  • Warhammer 40,000 Rulebook (Digital Edition) (7th Edition), pp. 275, 284, 331, 381, 541-542
  • White Dwarf 189 (UK), "Vindicare Imperial Assassin: Imperium," by Andy Chambers, pp. 13-16
  • White Dwarf 190 (UK), "Callidus Imperial Assassin: Imperium," by Ian Pickstock, pp. 21-24
  • White Dwarf 191 (UK), "Assassin!: Imperial Eversor Assassin," by Ian Pickstock, pp. 11-14
  • Nemesis (Novel) by James Swallow
  • Seventh Retribution (Novel) by Ben Counter
  • Inquisitor (Novel) by Ian Watson
  • Harlequin (Novel) by Ian Watson
  • Chaos Child (Novel) by Ian Watson
  • Warhammer Community - Heresy Thursday – Decapitate Your Enemies With the Clade Adamus Assassin
Officio Assassinorum Temples
Major Temples Callidus TempleCulexus TempleVindicare TempleEversor Temple
Minor Temples Adamus TempleVenenum TempleVanus TempleMaerorus Temple